I, Luke T. Shumaker, am the sole author of the added code.
I did not reference CVTUTF when writing it. I did reference the Unicode standard (15.0.0), the Wikipedia article on UTF-8, and the Wikipedia article on UTF-16. When I saw some tests fail, I did reference the old deleted code (but a JSON-specific part, inherently not as based on CVTUTF) to determine that script_safe should also escape U+2028 and U+2029.
I targeted simplicity and clarity when writing the code--it can likely be optimized. In my mind, the obvious next optimization is to have it combine contiguous non-escaped characters into just one call to fbuffer_append(), instead of calling fbuffer_append() for each character.
Regarding the use of the "modern" types uint32_t, uint16_t, and bool:
ruby.h is guaranteed to give us uint32_t and uint16_t.
Since Ruby 3.0.0, ruby.h is guaranteed to give us bool... but we support down to Ruby 2.3. But, ruby.h is guaranteed to give us HAVE_STDBOOL_H for the C99 stdbool.h; so use that to include stdbool.h if we can, and if not then fall back to a copy of the same bool definition that Ruby 3.0.5 uses with C89.
[ruby/json] Adjust to the CVTUTF code being gone
I, Luke T. Shumaker, am the sole author of the added code.
I did not reference CVTUTF when writing it. I did reference the
Unicode standard (15.0.0), the Wikipedia article on UTF-8, and the
Wikipedia article on UTF-16. When I saw some tests fail, I did
reference the old deleted code (but a JSON-specific part, inherently
not as based on CVTUTF) to determine that script_safe should also
escape U+2028 and U+2029.
I targeted simplicity and clarity when writing the code--it can likely
be optimized. In my mind, the obvious next optimization is to have it
combine contiguous non-escaped characters into just one call to
fbuffer_append(), instead of calling fbuffer_append() for each
character.
Regarding the use of the "modern" types
uint32_t,uint16_t, andbool:support down to Ruby 2.3. But, ruby.h is guaranteed to give us
HAVE_STDBOOL_H for the C99 stdbool.h; so use that to include
stdbool.h if we can, and if not then fall back to a copy of the
same bool definition that Ruby 3.0.5 uses with C89.
https://github.com/ruby/json/commit/c96351f874